.Find the Z-sCore corresponding to the given value and use the z-SCore to determine whether the value is unusual. Consider a score to be unusual if its z-score is less than -2.00 or greater than 2.00. Round the z-score to the nearest tenth if necessary. A test score of 50.0 on a test having a mean of 69 and a standard deviation of 10.

a. 1.9; not unusual
b. -19; unusual
c. -1.9; unusual
d. -1.9; not unusual